//this is the width of the designer page
$designWidth: 750;
$remCount: 10;
$rem: (750 / 10) px;
@function ptr($px) {
  @return $px*($remCount/$designWidth)*1rem;
}

//div {
//  width: px2rem(10);
//}
body {
  font-size: ptr(16);
}








